1) Field of the Invention
The invention herein relates to an improved structure hoist-use base hoisting ring, the improved structure of which provides for lifting the load of the weight at the bottom end of the hoisting ring, with the hoisting ring lifting the weight having adjustable rotation capability. Furthermore, the said structure includes a planar bearing nested in a cylindrical base mount and provides for its sleeving over the periphery of the neck of a bottom mounting bushing such that its top surface is against the bottom side of a circular top mounting bushing to thereby achieve simplification and convenience, which is among the features of the present invention.
2) Description of the Prior Art
Hoist-use base hoisting rings are utilized for weight, machined object, and support plate lifting and transporting applications. The conventional structure (referring to FIG. 1) is typically comprised of a U-shaped clevis 3 movably suspended from the two sides at the lower end of a cylindrical base mount 2 as well as a matching circular top mounting bushing 4 at the upper section and a bottom mounting bushing 5 at the center section having an upwardly projecting neck 51 and a passageway 52 that are situated over the top and bottom lateral surfaces of the bore 21 through the interior portion of the cylindrical base mount 2, enabling the installation of a bolt 6 into the top mounting bushing 4 center section and downward through the bottom mounting bushing 5 and the fastening and positioning of its threaded section 61 into the threaded hole P1 of a weight P at the lower end.
However, when chain from a crane installation involved in the lifting operation is connected to the upper extent of the hoisting ring in such a structure, due to the heavy load of the weight P at the bottom end, the fastened bolt 6 is pulled downward such that the top mounting bushing 4, the cylindrical base mount 2, and other components are all in a state of critical stiction; as a result, the interconnective relationship of the top mounting bushing 4, the cylindrical base mount 2, and the bottom mounting bushing 5 is disposed in a revolvable concentrically linked arrangement, but given that each component is subjected to the “vertical downward pulling force” produced by the heaviness of the weight P and thus each component is actually in an “impeded state”, the achievement of convenient rotatable operation is not possible.
After the weight P is hoisted and when it is necessary to partially turn or adjust the weight P for machining, inspection, alignment, or other required tasks, the operation is quite strenuous and difficult, and even essentially impossible to accomplish, resulting in considerable inconvenience.
Contrastively, when the weight is transported, and the hoisting hook (including the upper section chain or steel cable) at the upper extent of the hoisting ring twists around as the lifted weight P is moved, the original position of the weight P varies with the rotation of the chain or steel cable at the upper extent of the hoisting hook because of the impeded state of each component, resulting in extreme inconvenience in that a worker cannot operationally transport the weight P to the exact, expected final position.